Anti-rattle latchbolt



Dec. 15, 1959 E. L. SCHLAGE 2,917,336

ANTI-RATTLE LATCHBOLT Filed April 8; 1957 INVENTOR. ERNEST L. SCHLAGE I711% my 7 A r rowers United States PatentO ANTI-BATTLE LATCHBOLT ErnestL. Schlage, Burlingame, Calif., assignor to Schlage Lock Company, acorporation Application April 8, 1957, Serial No. 651,364 1 Claim. (Cl.292-2) This invention relates to door latches and more particularly tothe provision of means for preventing a latch bolt from rattling againstits associated'strike. This application is a continuation in part ofcopending applica-' inner edge of the opening in the strike plate, whichthe bolt enters, for holding the door closed against its associatedstop.

Ideally, the strike plate should be mounted so that when the boltsplanar surface is in engagement with the edge of the strike opening thedoor will fit snugly against its stop and be held relatively immovablebetween such edge and such stop. Due to the flexibility, fatigue, andshrinkage of the materials of which the door and frame are usually madeand to the settling of the structure in which the door may be mounted,the above described Even though the latch ideal condition is rarely met.and strike plate may be carefully and accurately installed, a shortinterval of use ordinarily destroys such accuracy and renders the closeddoor loose with respect to the stop. The door may then be oscillated,rattling the latch bolt against strike.

Not only may such rattling be annoying to the building inhabitants andpersons using thedoor, but unauthorized entry may be permitted thereby.Where a gap exists between a door and its associated stop, it is oftenpossible for unauthorized persons to slip a thin card or the like intosuch gap and between the latch bolt and the. strike to cam the boltrearwardly and open the door.

It is therefore a main object of this invention to provide means forpreventing the rattling of a latch bolt against its associated strike.

It is another object of this invention to provide means to assure thetight engagement of a closed door with its associated stop.

Still another object of this invention is the provision of a springprojected wedge to yieldably urge a latch bolt and a door upon which itis mounted toward the door stop.

It is a further object of this invention to provide means obviating thenecessity of accurately positioning a latch strike with respect to adoor stop, and yet retaining the desirable characteristics of accurateand careful installation of a door latch assembly.

Other objects and advantages of this invention will become apparent fromthe following description taken in connection with the accompanyingdrawings in which:

Fig. 1 is a horizontal, sectional view taken through a latch housing andthe portion of a door and frame adjacent thereto showing one form of theantirattle member a vertical,- planar surface 21 adapted to engage edge8 .of strike plate 5 to hold the door in the closed position.

. for s'ecurement to the aforementioned retractor assembly.

2,917,336 .Pat ented Dec. 15, 1959 of this invention in operativerelation to the door latch ified form of dead latch member;

In detail, referring to Fig. 1-, the device of this invention isdescribed for use with a conventional vdoor latch which includes a latchhousing I mounted in a bore 2 in the free edge of :adoor 3. Door 3 isadapted to swing about its hinges (not shown) in and out of frame 4 uponwhich is mounted a strike plate 5 having a central opening 6 therein.When door 3 is in the closed position shown it is adapted to abutstop 7which is mounted on frame 4 opposite the operative edge 8 of opening 6.

The open forward end 9 of housing 1 is flanged so as to be securedbetween face plate 10 and back plate 11 which are joined together andsecured to door 3 by screws 12(Fig. 2). The other or rear end 13 ofhousing 1 is closed except for a central aperture 14. Face plate 10 iscentrally apertured as at 15 to permit reciprocable latch bolt 16 toproject therethrough.

Latch bolt 16 is formed, outwardly of face plate 10, to a cross sectioncongruent withopening 15 and said latch bolt is provided with forwardlydirected shoulders 17, 18 to actas stops to prevent withdrawal of bolt16 through face plate 10.

Extending rearwardly from said latch bolt is latch bar 19, therearwardly directed end of which extends through aperture'14. Latch bar19 is provided for the purpose.

of connecting bolt 16 to a conventional retractor (not shown) toreciprocate latch bolt 16 longitudinally of housing 1.

The forward end of bolt 16 is provided with strike surface 20 inclinedto the longitudinal axis of housing 1v and bolt 16. The front of saidbolt is also formed with Extending rearwardly from latch bolt 16, withinhous= ing 1, is tubular guide 22 which slides. on spring guide rod 23,extending forwardly from rear end 13 of housing 1. Surrounding tubularguide 22 and rod 23 is a helical coil spring 24 which abuts guide member27 at the rear face of bolt.'16 and plate 25 adjacent closed end 13 ofhousing 1. for the purpose of projecting latch bolt 16. Plate 25 isprovided with rearwardly extending dogs 26 In operation of the latchdescribed, upon swinging door 3 toward frame 4 strike surface 20 engagesstrike plate 5 thereby camrning latch bolt 16 inwardly of housing 1.When door 3 engages stop 7 the correct position lof strike plate 5 issuch that the outer or forward end of bolt 16 enters opening 6, andplanar, strike-edge-engaging surface 21 slides closely adjacent edge 8of such opening. Bolt 16 thereby prevents opening of door 3 except byretraction of said latch bolt.

In order to prevent the aforementioned rattling of latch bolt 16 inopening 6, where the adjustment of strike plate edge 8 and door stop 7is such that the distance therebetween is appreciably greater than thedistance between planar surface 21 and the inner face of door 3, thelatch mechanism described is provided with antirattle element 30. Suchelement is formed with a wedge surface 31 inclined to the longitudinalaxis of housing 1 opposite to the inclination of strike surface 20.Latch bolt 16 is recessed, as at 46, along stiike-edge-engaging surface21 in order to slidably receive a portion of'antirattle element 30therein. Inclined surface 31 of said antirattle element intersectssurface 21 near the outer end of latch bolt 16 in order that antirattleelement 30 will enter opening 6 in strike plate under all conditions ofinstallation. Hence, even when strike plate 5 is originaJly installedaccurately with respect to door stop 7 the outer end of antirattleelement 30 will project slightly into opening 6. i

Element 30 is reciprocable longitudinally of housing 1 and is providedwith a rearwardly extending tubular guide 33 reciprocable on springguide rod 34. Surrounding tubular guide 33 and rod 34 is a helical coilspring 35 which abuts element 30 on one end and plate 25 on the other.Spring 35 therefore yieldably projects element 30 outwardly ofhousing 1. Element 30, tubular guide 33, guide rod 34, and spring 35are. seen to be preferably positioned on the opposite side of latch bar19 from tubular guide 22, guide rod 23, and spring 24.

Opening 15 in face plate is recessed at one edge, as at 36, to allowpassage of element 30. A forwardly directed shoulder 38 may also beprovided on element 30 for engaging the rear side of latch bolt 16. Inthis manner, when element 30 is projected to its foremost position withshoulder 38 in engagement with said rear end of bolt 16, spring 35 alsoacts to project said bolt. An angle guide 39 having one bifurcated leg40 positioned between a pair of shoulders 41, 42 on element 30 and theother leg 43 parallel to and slidable along latch bar 19 may be providedto additionally guide element 30 in a parallel path to the longitudinalaxis of housing 1.

In operation, the forward end of element 30 is adapted to wedge betweenplanar surface 21 of latch bolt 16 and edge 8 of strike 5 to yieldablyurge door 3 against stop 7. Therefore, any difference in adjustment of.strike plate 5, allowing an appreciable space to exist between surface21 and edge 8 when door 3 is in tight engagement with stop 7, is takenup by antirattle element 30. It is obvious that the greater the spacebetween surface 21 and edge 8 the farther element 30 will be projectedby spring 35 in order to take up the slack. Because of the small angleof inclination and the available length .of surface 31 the range ofoperation of element 30 is quite large.

The fact that antirattle element 30 is recessed into thestrike-edge-engaging surface 21 of latch bolt 16 provides for greaterstrength in the outer end of element 30. Said outer end need not be verythin in section in order to provide a wedging action when the spacingbetween surface 21 and edge 8 is only very slight. The element 30 is, ofcourse, subject to repeated shocks in opening and closing the door maybe formed to a relatively husky section to withstand such shocks andstill present a wedging surface to edge 8 under all conditions.

In the modifications of Figs. 3 and 4 the antirattle elements 50 and 60,respectively, are shown displaced from the central position of Fig. 1.Otherwise the construction and operation of elements 50 and are similarto element 30. The positioning of elements 50 and 60 provides for theconcurrent use of deadlocking plungers 51, 61 (Figs. 3, 4 respectively)with the latch unit. Plungers 51, 61 operate in accordance with theprinciples described in Patent No. 2,613,094, issued October 7, 1952,and are for the purpose of preventing retraction of latch bolt 16 byunauthorized means when the spring projected plungers are held in aretracted position by the surface of strike plate 5.

The latches of Figs. 3 and 4 therefore not only provide the antirattlefeature but are also deadlatches. In Fig. 3

the plunger 51 rides alongside the flat surface 21 of bolt 16, whereasin Fig. 4 plunger 61' is guided in a recess 62 in bolt 16. In eithercase, plungers 51, 61 may be separately spring urged to a projectedposition in a manner similar to elements 30, 50 and 60.

Although the above description is in detail it is intended that thescope of the invention be restricted only by the following claim andequivalent structures.

I claim:

In combination with a spring projected latchbolt having a flat faceadapted to lie alongside an edge of a strikeplate opening when said boltis projected into such opening, an elongated antirattle element having afirst portion of constant cross section and a second, adjoining portionof the same width as said first portion and progressively decreasingthickness terminating in one end of substantial thickness providing awedge surface inclined to the longitudinal axis of said element, meansproviding an elongated recess in said bolt opening outwardly of saidface and extending in the direction of projection of said bolt, saidrecess being of a constant depth greater than the thickness of said oneend of said element and less than the thickness of said first portion,said element being slidably mounted in said recess with said wedgesurface extending from said one end behind said face outwardly of saidface, and means yieldably projecting said element in said direction forengaging the part of said wedge surface that extends outwardly of saidrecess with such edge for progressively urging said bolt face away fromsuch edge.

